This invention relates to a test apparatus for testing electric characteristics of a test object such as a flexible circuit board which is generally called a flexible printed circuit (FPC).
For example, Japanese Patent Publication (JP-B) No. H7-19812 discloses a test apparatus for testing a semiconductor device or a LCD (Liquid Crystal Display) which has a number of electrodes arranged at a fine pitch. The test apparatus comprises an insulating film provided with a plurality of contacting portions. The contacting portions comprise a plurality of conductive wires formed as probes. Upon carrying out a testing operation, the contacting portions are brought into contact with the electrodes of the substrate to test electric characteristics of the substrate. In order to indicate relative positioning between the electrodes of the substrate and the contacting portions of the insulating film, the insulating film is provided with a marking.
In case where the pitch is relatively large at the electrodes of the substrate and at the contacting portions of the insulating film, positioning therebetween can easily and accurately performed by visual observation.
However, if the pitch is extremely small, it is difficult to accurately position the electrodes of the substrate and the contacting portions of the insulating film with respect to each other.